MAP sensor feed voltage lost
#1
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The feed voltage from the PCM to the MAP was lost for some reason. The PCM will only send 0.5v or less to the MAP sensor (checked @ the PCM, as well as, the MAP sensor) which causes a low input voltage code. The issue is internal to the PCM.
I sent a new reference voltage to the MAP sensor from an unused 5v PCM source of which has corrected the problem. The original pin# for the MAP feed voltage is #64 on the blue connector & the new feed (jumper) comes from #71 (unused) on the blue connector. It's a 98 PCM. Anyone ever run into this before?
I sent a new reference voltage to the MAP sensor from an unused 5v PCM source of which has corrected the problem. The original pin# for the MAP feed voltage is #64 on the blue connector & the new feed (jumper) comes from #71 (unused) on the blue connector. It's a 98 PCM. Anyone ever run into this before?
#2
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No one?
Probably, when this happens, the PCM is replaced. Will leave it posted for the archives as an alternative when a PCM feed voltage is lost. This problem may be a sign that the PCM is crapping out & I do have a spare PCM that only needs a crank relearn, should that happen.
Probably, when this happens, the PCM is replaced. Will leave it posted for the archives as an alternative when a PCM feed voltage is lost. This problem may be a sign that the PCM is crapping out & I do have a spare PCM that only needs a crank relearn, should that happen.